Human reproduction 140

1) Which of the following is NOT true about protein and peptide hormones?
A. include follicle-stimulating hormone (FSH), luteinizing hormone (LH), andprolactin (PRL)
B. receptors are large protein molecules with extracellular, transmembrane, andintracellular domains
C. when hormone binds the receptor, a biochemical change is triggered in cellcytoplasm causing the release of a second messenger (e.g., cAMP)
D. pass through the phospholipids bilayer of the plasma membrane
E. some of these hormones are released from the hypothalamus

2) Which one of the following hormones has its receptors located within the cytoplasm ornucleus of target cells?
A. Prolactin
B. Luteinzing hormone
C. Follicle-stimulating hormone
D. Progesterone
E. Gonadotropin releasing hormone (GnRH)

3) Which one of the following hormones is NOT secreted by the adenohypophysis(anterior pituitary)?
A. Prolactin
B. Oxytocin
C. Luteinzing hormone
D. Follicle-stimulating hormone

4) Prostate glands enlarge in older men in response to which hormone?
A. testosterone
B. dihydroxytestosterone (DHT)
C. androstenedione
D. dihydroepiandrosterone (DHEA)

5) Which of the following is FALSE about steroid binding globulins?
A. steroid binding globulins are carrier proteins that attach to steroid hormones
B. bound steroids affect target cells
C. 2-3 % of estradiol is free in the blood
D. concentration of steroid binding proteins change with pregnancy and obesity
E. binding globulins regulates the availability of steroid hormones

6) Which of the following is true about melatonin?
A. high doses can inhibit reproductive gonadal systems in males and females
B. levels of melatonin in blood of pre-pubertal children rise markedly just beforeonset of puberty
C. causes a mild stimulant effect
D. dark exposure decreases melatonin secretion
E. synthesized by pituitary gland in central nervous system

7) Which of the following is NOT released by the pituitary gland?
A. GnRH (gonadotropin releasing hormone)
B. LH (luteinizing hormone)
C. Prolactin
D. Oxytocin
E. FSH (follicular stimulating hormone)

8) Which of the following is true about neurosecretory neurons?
A. Neurohormones are packaged into large granules and are released into spacesadjacent to axon ending
B. speed of nerve impulse is faster than a regular neuron
C. neurosecretory axons release LH and FSH
D. neurotransmiiters are released from the nerve terminus

9) Which of the following is FALSE about prolactin?
A. estrogen increases the response of prolactin-secreting cells in theadenohypophysis (anterior pituitary
B. prolactin releasing hormone is secreted by hypothalamus
C. high levels of prolactin can stimulate ovulation
D. prolactin enhances uterine contraction during labor
E. prolactin is released from the adenohypophysis (anterior pituitary)

10) Which of the following is true about the gonadal hormones?
A. Progesterone can cause positive feedback to hypothalamus
B. Steroid hormones are peptides
C. Inhibin acts directly on hypothalamus to suppress secretion of FSH
D. Activin opposes the action of inhibin
E. Follistatin binds to inhibin and blocks its action

11) Which of the following represent homologous development and are derived from thesame embryonic tissue?
A. female labia minora and male scrotum
B. female vestibular glands and male seminal vesicles
C. female clitoris glans and male penis glans
D. female oviducts and male epididymus
E. female cervix and male vasa efferentia

12) Which of the following is an example of a female sex accessory duct?
A. labia minora
B. clitoris
C. hymen
D. oviducts
E. vaginal introitus

13) Which of the following is an example of a female secondary sexual characteristic?
A. ovaries
B. clitoris
C. enlarged breasts
D. mons pubis
E. labia majora

14) What is the transparent membrane between oocyte and follicular wall in follicle?
A. zona pellucida
B. ovarian stroma
C. theca
D. granulosa
E. hymen

15) Ovarian steroid hormone secretions are influenced by which two pituitary hormones?
A. LH & GnRH
B. FSH & GnRH
C. inhibin and FSH
D. LH & FSH
E. activin & inhibin

16) During the follicular stage of the menstrual cycle, which hormone is most responsiblefor growth of follicles?
A. LH
B. Estrogen
C. Progesterone
D. FSH
E. GnRH

17) During the follicular stage of the menstrual cycle, which hormone is most responsiblefor growth of theca cells?
A. LH
B. Estrogen
C. Progesterone
D. FSH
E. GnRH

18) Which of the following are NOT controlled by LH?
A. ovulation
B. oocyte maturation
C. corpus luteum
D. conversion of androstenedione to estrogen by granulosa
E. production of androstenedione by theca

19) Which of the following is NOT true about the Δ5 pathway?
A. estrogen is main steroid produced by this pathway
B. active in tertiary follicles
C. supported mainly by LH
D. active in granulose cells
E. cholesterol is precursor to Δ5 pathway

20) Which of the following is true about the Δ4 pathway?
A. main activity is in luteal cells
B. Produces only progesterone
C. Main pathway in ovary during early part of follicular phase of menstrual cycle
D. Active in 20 graafian follicles in each ovary late in follicular phase

21) Which of the following is NOT true about oocytes arrested in first meiotic division?
A. present in primary follicles in newborns
B. present in secondary follicles
C. present in tertiary follicles
D. are haploid
E. are diploid

22) Which hormone is most responsible for triggering the completion of the first meioticdivision in oocytes?
A. Estrogen
B. Progesterone
C. LH
D. FSH
E. GnRH

23) A woman has ovulated consistently once a month throughout her reproductive life.However, this woman decided to become a nun and never had sexual intercoursethroughout her entire life. How many of her oocytes would have COMPLETE both stageone and stage two of meiosis?
A. 400-5000
B. 400-500
C. 40-50
D. 4-5
E. 0

24) The second meiotic division of the oocyte is completed when
A. sperm penetrates ovum in oviduct
B. ovum is released from ovary
C. graafian follicle forms
D. tertiary follicle forms from a secondary follicle
E. secondary follicle forms from a primary follicle

25) When one oocyte goes through meiotic division, how many mature haploid oocytes(ootids) are produced?
A. 4
B. 3
C. 2
D. 1

26) Which part of the uterus is shed during menstruation?
A. perimetrium
B. myometrium
C. cervix
D. stratum basalis
E. stratum functionalis

27) Which hormone is most responsible for ejection of milk from the nipple bycontracting myoepithelial cells?
A. prolactin
B. estrogen
C. oxytocin
D. LH
E. Progesterone

28) In a woman with a 28 day cycle, during days 6-14, which hormone is most directlyresponsible for growth of the uterine endometrium?
A. progesterone
B. testosterone
C. estradiol
D. LH
E. FSH

29)In a woman with a 28 day cycle, during days 15-28, which hormone is most directlyresponsible for preparing the uterus for implantation of the embryo?
A. LH
B. Progesterone
C. FSH
D. Estradiol
E. Testosterone

30) By day 3 of the menstrual phase, which hormone is NOT moderately elevated?
A. LH
B. FSH
C. Estradiol
D. Progesterone

31) In a woman with a 28 day cycle, estrogen levels peak during which days?
A. days 8-9
B. days 10-11
C.days 12-13
D. days 14-15

32) During the mid follicular phase
A. low estrogen levels stimulate gonadotropin output because of absence of negativefeedback
B. moderate estrogen levels exert negative feedback on gonadotropin secretion
C. very high estrogen levels exert positive feedback on gonadotropin secretion
D. progesterone levels are high
E. progesterone levels are moderate

33) Late in follicular phase, there is an increase in GnRH which produces a dramaticsurge of LH with a smaller rise in FSH. The activity of what possible hormones may beresponsible for the lower production of FSH compared to LH during this time?
A. inhibin and/or activin
B. inhibin and/or follistatin
C. activin and /or follistatin
D. inhibin and/or progesterone
E. follistatine and/or progesterone

34) High progesterone levels in the blood indicates?
A. menstruation
B. early follicular phase
C. mid follicular phase
D. late follicular phase
E. luteal phase

35) During mid luteal phase
A. progesterone and estrogen levels are similar
B. estrogen levels are much higher than progesterone
C. progesterone levels are much higher than estrogen
D. endometrium begins to degenerate

36) During the mid luteal phase
A. low estrogen levels stimulate gonadotropin output because of absence of negativefeedback
B. low progesterone levels stimulate gonadotropin output because of absence ofnegative feedback
C. High progesterone levels exert negative feedback on gonadotropin secretion
D. High progesterone levels exert positive feedback on gonadotropin secretionE. High estrogen levels exert positive feedback on gonadotropin secretion

37) Which of the following does NOT contribute to seminal fluid?A. prostate glandB. bulbourethral glandsC. seminal vesiclesD. spermE. spongy urethra (CORRECT)

38) Which of the following is NOT true about spermiogenesis?
A. spermatids transform into spermatozoa (sperm cells)
B. supported by testosterone
C. sperm heads are embedded in tiny pockets in Sertoli cell membrane
D. an elongated flagellum grows out of posterior end of sperm cell
E. sperm heads are released from Sertoli cells

39) As a primary spermatocytes complete the first stage of meiosis, which of thefollowing is NOT true for the resultant daughter cells?
A. have 23 chromosomes
B. are haploid (1N)
C. are called secondary spermatocytes
D. are called spermatids

40) The entire process of spermatogenesis to spermiation takes
A. 6-7 seconds
B. 6-7 minutes
C. 6-7 days
D. 65-75 days
E. 65-75 weeks

41) Human males produce sperm at a rate of
A. 1 sperm per second
B. 10 sperm per second
C. 1,000 sperm per second
D. 100,000 sperm per second
E. 1,000,000 sperm per second

42) Sperm are produced within the
A. seminiferous tubules
B. rete testes
C. epidydimus
D. vas deferens
E. vasa efferentia

43) Which of the following is NOT true about Sertoli cells?
A. releases inhibin
B. form tight junctions which form a blood-testes border
C. are phagocytic
D. produces most of the testosterone in human males
E. secrete androgen-binding proteins

44) Which is NOT true about gonadal development in the embryo and fetus?
A. Germ cells begin to penetrate indifferent gonads during 4th or 5th week ofdevelopment
B. indifferent gonads develop during the 5th week of development
C. during the 6th week indifferent sex accessory ducts (Wolffian and Mullerianducts) develop
D. external genitalia are indifferent during 6th week of lifeE. If Y chromosome is present the testes will start developing in the 9th week ofdevelopment

45) Which of the following is NOT true about the SRY (sex-determining region of the Y)gene?
A. stimulates the production of TDF (testes-determining factor)
B. “master switch” that turns on these testis forming genes
C. causes the mullerian duct system to develop
D. initiates development of seminiferous vesicles in the medullary region of thegonad

46) If a male (XY) rat embryo is orchidectomized so that no testosterone or mullerianinhibiting substance is produced, which of the following will be the outcome of the sexaccessory organ development?
A. only Mullerian duct system develops
B. only Wolffian duct system develops
C. both Mullerian and Wolffian duct systems develop
D. neither Mullerian or Wolffian duct systems develop

47) 5-alpha-reductase is responsible for which of the following?
A. conversion of estrogen to progesterone
B. conversion of estrogen to testosterone
C. conversion of dihydroxytestosterone (DHT) to testosterone
D. conversion of testosterone to dihydroxytestosterone (DHT)
E. conversion of estrogen to dihydroxytestosterone (DHT)

48) Which of the following is TRUE regarding psuedointersex individuals?
A. possess an ovitestis
B. possess gonads of the chromosomal sex, but external genitalia and secondary sexcharacteristics that look like the opposite sex
C. possess an ovary on one side and a testis on the other
D. possess external genitalia of the chromosomal sex but gonads of the opposite sex

49) Which of the following is NOT a characteristic of Klinefelter's syndrome?
A. tall male with acne
B. 47:XXY
C. female like breasts
D. small external genitalia
E. sterile cryptorchid testes

50) Which of the following is NOT true aneuploidy?
A. embryos with one too few (45: monosomy) chromosomes
B. embryos with one too many (47: trisomy) chromosomes
C. Trisomy 21 (Down’s Syndrome)
D. Embryos that have more than two full sets of homologous chromosomes